Looping Geometry | Autodesk Civil 3D Subassembly Composer

Following with the pattern of our previous posts, in this post, we'll review an additional workflow tool referred to as "Looping" or "Loop Geometry" in Subassembly Composer.

Previously, we've reviewed packet settings, how to create a simple SAC using basic tools, how to create a rounded shoulder using auxiliary points, daylight rounding and switches.

If you want to watch a video tutorial of this post, click here.

What does looping do?
Looping repeats specified links until they reach a Surface Target or until they are repeated a specified number of times. A bench is a good example of this.

Let's jump in! We'll deconstruct a looping subassembly and look at how it's been created.

  1. In Subassembly Composer, we have a flowchart with points already in place and a decision being made.
  2. If we take a look at our staring point, we have an origin point and then an auxiliary point underneath it. The auxiliary point (AP1) in this case is the surface.
  3. From that auxiliary point (AP1), there is a decision. It will either Daylight or Bench. We want to focus on the Bench.
    Daylight: Create a slope to surface.
    Bench: It will connect to the next point (P3&L2), then a swale (P4&L3), creates the swale (P5&L4) and then looks for the surface (P5&L4). If it doesn't find the surface, it will repeat. (You don't have to create a swale in this bench, but in this example, we have.)
  4. In this loop, you can see the "Loop Repetition" is set to "10", which means this loop will repeat 10 times unless it reaches the surface before that.

And that's looping! Incredibly simple, right? If you want to learn more about Subassembly Composer, click here